Data from this laboratory describing genetic polymorphisms involving human pancreatic and salivary amylases will be extended. The two loci are closely linked on chromosome 1 and control variant enzymes in the pancreas (Amy2) and salivary glands (Amy1). The objectives are: (1) Biochemical definition of these two polymorphic enzymes, with specific emphasis on determining whether the two genes arose from a duplication, by analyzing the molecular similarities and differences through electrophoresis, amino acid analysis, and polypeptide fingerprinting. (2) Extension of molecular studies to other mammalian species to evaluate evolutionary events and the developmental genetics of amylase enzymes. (3) Linkage analysis within these loci and also with other genetic factors (chromosome variants, polymorphic blood and serum factors, heritable disease). Particular emphasis will be placed on linkage group I. (4) Evaluation of associations with heritable and nonheritable disease states in man, including an evaluation of pancreatic function. A discontinuous buffer system, sheet polyacrylamide gel will be utilized to identify electrophoretic variants of the pancreatic and salivary amylases. The enzymes will then be purified by ethanol extraction, glycogen precipitation and gel filtration chromatography. The structures of the two amylase proteins will be compared by peptide mapping and amino acid analysis. Recently initiated studies will be pursued to explore possible differential development of the expressions of the two loci. In addition, other mammalian amylases will be investigated to shed light on the evolution of the human amylase expressions.